944 stubs/CV's OR Type 1's for Frankenstein Setup?, Parts have arrived! Options

[Chris H.]

Goooood Morning,

So...my outer CV's seem to be shot. They are 914 and original 40 year olds. I popped another one last night. Tow truck ride! Yaaaay! Dang those things make a terrible noise when they come undone don't they? This is the 2nd one to pull this on me (other side last time). The last time the inner race worked its way loose. Guessing the same thing happened again. My axles are Subaru on one side, 914 on the other (sway-a-way).

Options:

- Get new Type 1 CV's. Looks like Tangerine and PMB carry them. One has the lip machined. Supposed to be very strong. My axles have very little angle to them. The Type 1's are being used on pretty powerful cars, so they SHOULD hold up. Mine's just ~230 hp (maybe) compared to some race cars that are far higher.

- Go with 951's, which are a stronger. Spent a lot of time figuring out what's needed and I THINK I have it.

Based on Aarons diagram (a tribute to Miles (IMG:style_emoticons/default/biggrin.gif) ) this is the standard setup:



I'd be going half way with this. Don't need anything to the right of the axle.

Questions:

1. I have re-drilled 914-4 rear hubs. Is the 951 stub (951 331 231 01) splined the same so it fits? Aaron's diagram notes a pre-'74 911 stub which I believe is the same spline count based on 20 searches (IMG:style_emoticons/default/biggrin.gif) . Other threads also mention you can use 914-6 stubs which should have the same spline count as the 4's right (IMG:style_emoticons/default/confused24.gif) ? Pretty sure I'm right but would hate to be wrong.

2. Does anyone make the spacer that is needed or found one that works that's pre-made? I see there is an option to machine off a portion of the hub so it matches. Is that a better idea?

If I can use the existing re-drilled 914-4 hub I would need the following parts:

- 951 stub axle part # 951 331 235 01
- 33 spline 944 CV part # 944 331 901 00
- spacer (or machine the excess off of the hub)

Cost difference is about $200 total.

What do the experts think?

[Chris H.]

Did a few searches on unrelated topics and found some incomplete threads, then realized I never finished this one. Also got quite a few PMs on the subject so I thought I'd close it out. Still happy to answer questions, but at least the thread is complete.

I confirmed the issue that was causing the multiple problems was the simple fact that the 914 CVs were worn and had too much play in them. This caused them to move around too much, which would either cause the Subaru end to slip out of its sleeve (1x) or the 914 CV to wobble into a precarious position which causes the cage to crack and break. Moral of the story...if you're raising HP, check the CVs. Replace them if there is the slightest question.

Here's a comparison of good vs bad:


https://www.youtube.com/watch?v=P-SMeg6ACEk


As Chris Foley described in another CV thread, see how there is no resistance with the "bad" one? You could make it a few miles, but not too far.

As usual, Bob knew exactly what I needed. Although a new Type 1 CV would probably have been fine, Bob had these cool adapters that allowed me to use 944 CVs WITHOUT changing the hubs/stubs. Here's how:

The EARLY 944 CV joint, part # 944.331.901.00 has the same spline count as a 914 axle so it fits on the 914 axle. You can't just bolt it to the 914 hub because it is larger and has more bolts. Here's the magic part....part of the Renegade Hybrids axle upgrade kit (called "axle flanges" I think) is an adapter that lets you bolt the 914 hub to the larger 911 OR 944 CV. Basically bolts to the 914 hub, then you bolt the 944 CV joint to the other side. If you have a stock axle you will need to remove some material from the inner portion since the 944 CV is slightly thicker. Not necessary with the sway-ways I have.

Pics:



From the RH site, I THINK the arrowed part is the adapter. With the full Renegade kit you would do one on each end, so 4 total. I believe they sell them separately as well.

Here it is in the wild:



Comparison of the two axles:



This also extends the axle itself by more than an inch, which is good since the Subaru end floats unattached unlike a Porsche CV and in extreme conditions can come out of it's end which SUCKS (you with me Ross ? (IMG:style_emoticons/default/biggrin.gif) ). To reinstall the axle I actually had to undo the shock from the trailing arm, lower it, install the axle end and raise it back up again. HIGHLY unlikely it will slip out now unless I get airborne...at which point I have other problems.